Generally, refrigerators are available in many styles, but the most common styles include both a refrigerator compartment and a freezer compartment, which may be side-by-side or one on top of the other. Often, refrigerator features such as ice making, ice crushing, water dispensing, precise temperature and/or humidity control, vacuum packaging, thawing, and fast chilling are available. All of these features typically require some type of utility, such as water, chilled air, or mechanical power to provide the benefit.
Newer concepts in refrigeration have included modular units which fit within a refrigerated compartment in order to provide the advantageous features above. Such modules are themselves a great convenience for the users of the refrigerators so equipped.